To buy xlPrecision 3.1:1) First, please download and try the Free Edition to
ensure that xlPrecision serves your needs.
2) Look over the table below to decide which xlPrecision edition you prefer.
3) Click on the 'BUY NOW' link for that edition.

Please Note:
The paid editions of xlPrecision all require that the Free
Edition be installed. The paid editions replace a single file,
xlPrecision.dll, with another file, also named
xlPrecision.dll, which is custom-compiled with the buyer's name and serial
number. This new file requires the supporting
files that are installed with the Free Edition.

Upgrades
If you buy one edition of xlPrecision and then later upgrade to a higher
edition, the upgrade price is the difference between the two editions' prices.
For example, if you buy the $5 edition and later want to upgrade to the $7
edition, the upgrade price is $2.

Of course, that only applies to upgrading to a higher edition of xlPrecision. It does
not apply to upgrading to any future versions of xlPrecision. Prices for
upgrading to future versions will be determined individually for each version.